In 2001, Ferriss founded BrainQUICKEN, an online nutritional supplements company. It made a product that was marketed as both BodyQuick and Brain Quicken, and whose ingredients included: “Cobalamin, Niacinamide, Folic Acid, 2-dimethylaminoethanol, Pyridoxine HCL, Pantothenic Acid (Calcium Pantothenate), Proprietary Cognamine™ Complex (including components of: Phosphatidylserine, Choline Bitartrate, Vinpocetine, Salix Alba, Thioctic Acid, L-Tyrosine, Ciwujia).”[24] It was claimed that this product would dramatically increase short term memory and reaction speed, taking effect within 60 minutes.[25][26] In 2010, he sold the company to a London-based private equity firm.[27][28]

In December 2008, Ferriss had a pilot on the History Channel, where he had one week to attempt to learn a skill normally learned over the course of many years. In the pilot episode he practiced yabusame, the Japanese art of horse archery.[39]

Ferriss is the author of three books, The 4-Hour Workweek, The 4-Hour Body, and The 4-Hour Chef; the first two were #1 New York Times bestsellers and the third was a #1 Wall Street Journal bestseller.[4][10][40]

Ferriss developed the ideas present in The 4-Hour Workweek while working 14-hour days at BrainQUICKEN.[3] Ferriss’s frustration and then personal escape from a workaholiclifestyle was the genesis of the book.[41]

The book received both positive and negative reviews. Leslie Garner of The Telegraph noted that, “With a punchy writing style and a higher literacy level than most flash-in-the-pan gurus, Ferriss has struck a chord with his critique of workers’ slavish devotion to corporations… Ferriss’s book skillfully compartmentalises, then pathologises, workers’ unhealthy relationships with office life.”[50] Dylan Tweney of Wired wrote, “Nearly every idea taken to extreme. No sense of work being anything more than a paycheck.”[51]

In 2009, The 4-Hour Workweek, Expanded and Updated was released by Random House and included multiple case studies authored by people who have utilized Ferriss’ methods.[52]

In December 2010, Ferriss’ second book, The 4-Hour Body: An Uncommon Guide to Rapid Fat-Loss, Incredible Sex, and Becoming Superhuman, was published by Crown.[56] The book covers more than 50 topics, including rapid fat loss, increasing strength, boosting endurance, and polyphasic sleep.[57] Ferriss also introduces his version of the Slow-Carb Diet, which involves the elimination of starches and anything sweet (including fruit and all artificial sweeteners) and a strong preference for lean protein, legumes, and vegetables.[58]

For the book, Ferriss interviewed more than 200 experts over a three year period. The experts ranged from doctors to athletes to black-market drug salesmen.[59] He said that he had recorded every workout he had done since the age of 18, and from 2004 (three years before his first book was published) he had tracked a variety of blood chemistry measurements, including insulin levels, hemoglobin A1c, and free testosterone.[56]

Ferriss’ third book, The 4-Hour Chef: The Simple Path to Cooking Like a Pro, Learning Anything, and Living the Good Life was released by Amazon Publishing in November 2012.[65]The 4-Hour Chef contains practical cooking and recipe tips and uses the skill of cooking to explain methods for accelerated learning.[66][67] Ferriss calls this capacity for mastering new skills in the minimum amount of time possible “meta-learning.”[66]

Ferriss is known for his application of both the Pareto principle and Parkinson’s Law to business and personal life.[81] He has also taken the position that technology such as email,instant messaging and internet-enabled PDAs complicate life rather than simplify it.[82][83] His teachings fit under the umbrella of what he calls “lifestyle design”, in which he promotes “mini-retirements” as an alternative to the “deferred-life” career path where one would work a 9 to 5 job until retirement in one’s 60s.[84][85] This involves breaking what he calls “outdated assumptions” and finding ways to be more effective so that work takes up less time.[84]

On his blog and later in his subsequent books, Ferriss applied this approach to areas other than business.[86] His book on fitness, for example, claims to provide the exercise and diet advice that produces the greatest results with the least amount of effort or time.[86] Ferriss uses the analogy of the “minimum effective dose” to describe this technique.”